Camelidae single-domain antibodies against yersinia pestis and methods of use

ABSTRACT

Single-domain antibodies (SAbs) against three  Yersinia pestis  surface proteins (LcrV, YscF, and F1), nucleic acid sequences encoding the SAbs, and polypeptides comprising two or more SAbs capable of recognizing two or more epitopes and/or antigens. The present invention further includes methods for preventing or treating  Y. pestis  infections in a patient; methods for detecting and/or diagnosing  Y. pestis  infections; and devices and methods for identifying and/or detecting  Y. pestis  on a surface and/or in an environment.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. application Ser.No. 16/023,723, filed Jun. 29, 2018, which was a continuation of U.S.application Ser. No. 13/906,386, filed May 31, 2013, which claimed thebenefit of and priority to U.S. Provisional Application No. 61/653,488,filed on May 31, 2012. The disclosure of each application isincorporated herein by reference, in its entirety.

RIGHTS OF THE GOVERNMENT

The invention described herein may be manufactured and used by or forthe Government of the United States for all governmental purposeswithout the payment of any royalty.

FIELD OF THE INVENTION

This invention relates generally to the field of single-domainantibodies. More particularly, it relates to single-domain antibodiesand polypeptides against Yersinia pestis, nucleic acid sequencesencoding the single-domain antibodies, and methods of using the same.

Background of the Invention Description of the Related Art

Increasing threats of bioterrorism have led to the development of newdiagnostic and therapeutic tools for pathogens that can potentially beused as biological weapons. Many of these pathogens, such as thecausative agents of plague, anthrax, and tularemia, are relatively easyto manipulate via genetic engineering and may be designed to evadedetection by sensor devices. Many of these biological weapons candidatesalso display resistance to current medical treatments. To be useful, adiagnostic tool must be sensitive and specific, as well as able towithstand the extreme conditions often encountered in the field. Thevalue of a therapeutic tool is largely determined by parameters such astoxicity, immunogenicity, and efficacy after administration. Inaddition, the therapeutic tool may be required to treat large number ofpeople in the event of a bioterrorism attack. All of these requirementshighlight the importance of a long shelf life and the production costsof biological weapon-related diagnostics and therapeutics.

Members of the family Camelidae, which includes alpacas, camels, andllamas, produce conventional antibodies, as well as antibodiesconsisting only of a dimer of heavy-chain polypeptides. The N-terminaldomain of these heavy chain-only antibodies, which is referred to asVHH, is variable in sequence, and it is the sole domain that interactswith the cognate antigen. Because of their small size (12-15 kDa, 2.2 nmdiameter, and 4 nm height), VHHs are also known as single-domainantibodies (SAbs), which are commercially-available as NANOBODIES(NANOBODY and NANOBODIES are registered trademarks of Ablynx N.V.,Belgium).

SAbs make attractive as tools for biological weapon detection due totheir high affinity and specificity for their respective targets andtheir high stability and solubility. Their small size gives SAbs theunique ability to recognize and bind to areas of an antigen that areoften not normally accessible to full-size antibodies due to sterichindrance and other size constraints. In addition, SAbs may beeconomically produced in large quantities, and their sequences arerelatively easy to tailor to a specific application. These properties,as well as their low immunogenicity, make SAbs uniquely suited fordetection, diagnostics, and immunotherapeutics.

SUMMARY OF THE INVENTION

The present invention includes a composition comprising at least onesingle-domain antibody against one or more Yersinia pestis (Y. pestis)surface proteins, in which the one or more Y. pestis surface proteinsare selected from the group consisting of YscF, F1, and LcrV, with eachsingle-domain antibody comprising four framing regions (FRs) and threecomplementarity determining regions (CDRs), in which the at least onesingle-domain antibody is selected from the group consisting of: (1) atleast one single-domain antibody comprising one CDR1 sequence selectedfrom the group consisting of SEQ ID NOs:1-7, one CDR2 sequence selectedfrom the group consisting of SEQ ID NOs:27-33, and one CDR3 sequenceselected from the group consisting of SEQ ID NOs:54-60; (2) at least onesingle-domain antibody comprising one CDR1 sequence selected from thegroup consisting of SEQ ID NOs:8-19, one CDR2 sequence selected from thegroup consisting of SEQ ID NOs:34-47, and one CDR3 sequence selectedfrom the group consisting of SEQ ID NOs:61-71, AEY, and PGY; and (3) atleast one single-domain antibody comprising one CDR1 sequence selectedfrom the group consisting of SEQ ID NOs:20-26, one CDR2 sequenceselected from the group consisting of SEQ ID NOs:48-53, and one CDR3sequence selected from the group consisting of SEQ ID NOs:72-78 and GNI,with the four framing regions of each single-domain antibody comprisingone FR1 sequence selected from the group consisting of SEQ IDNOs:79-102, one FR2 sequence selected from the group consisting of SEQID NOs:103-120, one FR3 sequence selected from the group consisting ofSEQ ID NOs:121-146, and one FR4 sequence selected from the groupconsisting of SEQ ID NOs:147-153.

In one embodiment, the at least one single-domain antibody is selectedfrom the group consisting of SEQ ID NOs:154-160, 168-185, and 204-217.In a further embodiment, the at least one single-domain antibody furthercomprises at least one of a protein tag, a protein domain tag, or achemical tag.

In one embodiment, the composition comprises a plurality ofsingle-domain antibodies against a single Y. pestis surface protein. Inanother embodiment, at least a portion of the plurality of single-domainantibodies is against different epitopes on the single Y. pestis surfaceprotein. In another embodiment, the composition comprises a plurality ofsingle-domain antibodies against at least two Y. pestis surfaceproteins.

In an alternative embodiment, the composition comprises a plurality ofsingle-domain antibodies further comprising a polypeptide. In oneembodiment, the plurality of single-domain antibodies comprising thepolypeptide are against a single Y. pestis surface protein. In anotherembodiment, at least a portion of the plurality of single-domainantibodies comprising the polypeptide are against different epitopes onthe single Y. pestis surface protein. In another embodiment, theplurality of single-domain antibodies comprising the polypeptide areagainst at least two Y. pestis surface proteins.

In a further embodiment, the polypeptide comprises a fusion protein. Inanother embodiment, the polypeptide comprises a multivalent proteincomplex, with the single-domain antibodies being joined together with atleast one linker molecule. In a further embodiment, at least one of theplurality of single-domain antibodies comprising the polypeptide furthercomprises at least one of a protein tag, a protein domain tag, or achemical tag.

The present invention further includes at least one isolated nucleotidesequence encoding the at least one single-domain antibody, wherein theat least one isolated nucleotide sequence is selected from the groupconsisting of SEQ ID NOs:164-170, 189-206, and 221-234.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph of the binding response of IgG isolated from an immunealpaca to Y. pestis YscF (ELISA).

FIG. 2 is a graph of the binding response of IgG isolated from an immunealpaca to Y. pestis F1 (ELISA).

FIG. 3 is a graph of the binding response of IgG isolated from an immunealpaca to Y. pestis LcrV (ELISA).

FIG. 4 is a graph of polyclonal phage ELISA testing after each round ofpanning to isolate YscF-specific phages.

FIG. 5 is a graph of the ELISA for the presence of YscF-specific SAbs inthe periplasmic extract of positive colonies.

FIG. 6 is a graph of polyclonal phage ELISA testing after each round ofpanning to isolate F1-specific phages.

FIGS. 7A-B are graphs of the ELISA for the presence of F1-specific SAbsin the periplasmic extract of positive colonies.

FIG. 8 is a graph of polyclonal phage ELISA testing after each round ofpanning to isolate LcrV-specific phages.

FIGS. 9A-B are graphs graph of the ELISA for the presence ofLcrV-specific SAbs in the periplasmic extract of positive colonies.

FIG. 10 is a protein sequence alignment of seven exemplary YscF SAbsaccording to the present invention.

FIGS. 11A-B are protein sequence alignments of eighteen exemplary F1SAbs according to the present invention.

FIGS. 12A-B are the protein sequence alignment of fourteen exemplaryLcrV SAbs according to the present invention.

FIGS. 13A-B are the double-referenced sensorgrams obtained on theBIACORE T200 sensor instrument for selected LcrV SAbs.

FIGS. 14A-B are the double-referenced sensorgrams obtained on theBIACORE T200 sensor instrument for the two LcrV SAbs demonstrating thebest binding capabilities.

FIGS. 15A-C are sequence alignments of nucleic acid sequences encodingthe exemplary YscF SAbs according to the present invention.

FIGS. 16A-H are sequence alignments of nucleic acid sequences encodingthe exemplary F1 SAbs according to the present invention.

FIGS. 17A-F are sequence alignments of nucleic acid sequences encodingthe exemplary LcrV SAbs according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention includes single-domain antibodies (SAbs) againstthree Yersinia pestis (Y. pestis) surface proteins (LcrV, YscF, and F1),the nucleic acids encoding the SAbs, and polypeptides comprising two ormore SAbs capable of recognizing one or more Y. pestis surface proteinsor epitopes. The present invention further includes methods forpreventing or treating Y. pestis infections in a patient; methods fordetecting and/or diagnosing Y. pestis infections; and devices andmethods for identifying and/or detecting Y. pestis on a surface and/orin an environment.

Y. pestis, the gram-negative bacillus that causes plague, is considereda Class A biological weapon. Y. pestis infections occur in threedifferent ways: infection of the lymph nodes (bubonic), the lungs(pneumonic), or the blood (septicemic). The most serious, contagious,and often fatal mode of plague is pneumonic plague, which may be causedby inhalation of contaminated respiratory droplets from another infectedperson or from intentional release of aerosolized plague pathogen. WhileY. pestis infections are treatable with antibiotics, diagnosis andtreatment are often delayed. In the case of pneumonic plague, the earlysymptoms such as fever, headache, and nausea may easily be mistaken formore common illnesses, delaying proper diagnosis and treatment duringthe early stages of the disease and greatly increasing the chances ofdeath. Untreated pneumonic plague has a mortality rate of almost 100%.In the case of battlefield personnel and persons stationed or living inrural areas, access to proper health care may be further limited bydistance and availability.

Of particular interest for detection and treatment are three Y. pestissurface proteins, LcrV, YscF, and F1. LcrV is a 37 kDa virulence factorthat is secreted and expressed on the Y. pestis cell surface prior tobacterial interaction with host cells, making it an excellent antigenicprotein for antibody capture. It has been shown that anti-LcrVantibodies can block the delivery of Yops, a set of virulence proteinsexported into the host cell upon contact. Additionally, it has beenshown that a single sensitive, specific antibody could be used tocapture LcrV from Y. pestis, Y. pseudotuberculosis, and Y.enterocolitica. The functional determination of LcrV provides a possiblereason for the success of anti-LcrV Ab immunotherapeutics as it ishypothesized that the anti-LcrV/Ab complex prevents the formation andfunction of the tip complex, thus interfering with the translocation ofvirulent Yops critical to infection. YscF has also been implicated asone of the “needle” proteins involved in T3SS injection of the virulentYops proteins across eukaryotic membranes upon cell contact. Recent workusing purified YscF to initiate an active immune response indicates thatYscF-vaccinated mice have significant protection to a Y. pestischallenge. As with LcrV, these data indicate that YscF is an excellentantigen target for immunotherapeutic uses. F1 protein, which is a Y.pestis capsule protein, has likewise been identified as a potentialtherapeutic target and is one of the principal immunogens in currentlyavailable plague vaccines. Among other roles, F1 is thought to beinvolved in preventing Y. pestis uptake by macrophages.

SAbs in general, including the presently disclosed Y. pestis SAbs,comprise four framework regions (FRs) interrupted by threecomplementarity determining regions (CDRs) to yield the followinggeneral structure:

-   -   FR1-CDR1-FR2-CDR2-FR3-CDR3-FR4.

Like many SAbs, the CDR3 sequence of the presently disclosed Y. pestisSAbs is generally the most crucial in determining antigen specificity.SAbs directed against a particular antigen generally demonstrate somedegree of homology or sequence identity between each FR and CDR. Wheretwo nucleotide or amino acid sequences are the same length when aligned,the term “sequence identity” as used herein relates to the number ofpositions with identical nucleotides or amino acids divided by the totalnumber of nucleotides or amino acids. The number of identicalnucleotides or amino acids is determined by comparing correspondingpositions of a designated first sequence (usually a reference sequence)with a second sequence. Where two nucleotide or amino acid sequences areof different length when aligned, the term “sequence identity” as usedherein relates to the number of positions with identical nucleotides oramino acids divided by the number of nucleotides or amino acids in thedesignated or reference sequence. Any addition, deletion, insertion, orsubstitution of a nucleotide or amino acid is considered a differencewhen calculating the sequence identity. The degree of sequence identitymay also be determined using computer algorithms, such algorithms mayinclude, for example, commercially-available Basic Local AlignmentSearch Tool, also known as BLAST (U.S. National Library of Medicine,Bethesda, Md.).

Y. pestis SAbs according to the present invention may be used ascomponents of in vivo and in vitro assays and may also be useddiagnostic testing and imaging. The generally low toxicity andimmunogenicity of SAbs further makes the present Y. pestis SAbspromising active and passive immunotherapeutic tools, particularly forself-administered fieldable therapeutics. In the case of an outbreak ora biological weapon attack, a self-administered treatment could providesufficient temporary immunity and sufficiently slow the onset andprogress of the disease to allow a person exposed to Y. pestis to reacha hospital for diagnosis and treatment. The SAbs may be introduced byany suitable method including intravenous and subcutaneous injection,oral ingestion, inhalation, and topical administration. The SAbs maybind to extracellular epitopes and antigens and may also bind tointracellular targets after introduction into the host cell byphagocytosis or other mechanisms. In addition, the Y. pestis SAbs may beuseful for decontamination and as field-stable capture elements forreal-time biological weapon detection and quantitation.

Many of the presently disclosed Y. pestis SAbs demonstrate fullfunctionality and high affinity for their respective antigen targets,which is likely due to the ability of SAbs to bind to protein cleftsthat are often inaccessible to larger, conventional antibodies. Thisability to access areas located in interior pockets may allowtherapeutic and detection tools based on the present Y. pestis SAbs todetect multiple strains of the pathogen, as well as related organisms inthe Yersinia genus. SAb-based tools and techniques may also be lesssusceptible to genetic engineering of pathogen surface proteins andepitopes designed to elude current detectors and to circumvent immunityconferred by conventional vaccination.

The Y. pestis SAbs according to the present invention may be quickly,easily, and inexpensively produced in large quantities in a bacterialexpression system such as E. coli with little or no loss of proteinactivity and little or no need for post-translational modification. Inaddition, the SAbs are stable within a wide range of temperature,humidity, and pH. This stability may allow for stockpiling and long-termstorage of the SAbs and SAb-based detection, diagnostic, and therapeutictools in preparation for Y. pestis outbreaks and/or a bioterrorismattack, all without the need for costly climate control and/ormonitoring. The stability of SAbs in extreme environments may furtherallow for reusable sensors and detection devices.

The following examples and methods are presented as illustrative of thepresent invention or methods of carrying out the invention, and are notrestrictive or limiting of the scope of the invention in any manner.Amino acid residues will be according to the standard three-letter orone-letter amino acid code as set out in Table 1. The materials andmethods used in Examples 1-4 are described, for example, in AntibodyEngineering, Eds. R. Kontermann & S. Dübel, Springer-Verlag, BerlinHeidelberg (2010) Isolation of antigen-specific Nanobodies, HassanzadehGhassabeh Gh., et al., Vol. 2, Chapter 20, pp. 251-266. Exemplarycombinations of individual FR and CDR regions are shown in Table 2, andcomplete SAb protein sequences isolated according to the followingExamples are listed in Tables 3, 5, and 7. Unique sequences (individualCDRs and FRs and complete SAb sequences) are each assigned a SEQ ID NO;sequences comprising less than four amino acids are not assigned a SEQID NO. As seen in FIGS. 10-12, some SAbs share 100% sequence identity inone or more CDRs and/or FRs because the SAbs are either fromclonally-related B-cells or from the same B-cell with diversificationdue to PCR error during library construction.

Example 1: Antibody Development and Construction of a VHH Library

All SAbs were developed using proteins (antigen) expressed from genesisolated from Y. pestis KIM5 (avirulent pgm−), which is similar insequence to the same protein set in Y. pestis virulent strains (pgm+).An alpaca was injected subcutaneously on days 0, 7, 14, 21, 28 and 35,each time with about 165 μg YscF antigen, about 160 μg F1 antigen, andabout 160 μg LcrV antigen. The same animal may be used for allexperiments, but multiple animals may also be used. On day 39,anticoagulated blood was collected from the alpaca for the preparationof plasma and peripheral blood lymphocytes. Using plasma from the immuneanimal, IgG subclasses were obtained by successive affinitychromatography on protein A and protein G columns and were tested byELISA to assess the immune response to YscF, F1, and LcrV antigens.FIGS. 1-3 are graphs of the immune response to YscF, F1, and LcrV,respectively, in both conventional (IgG1) and heavy chain (IgG2 & IgG3)antibodies. As seen in FIGS. 1-3, the IgG isolated from the immuneanimal exhibited a strong response toward all three antigens in bothtypes of antibody.

A VHH library was then constructed and screened for the presence of SAbsspecific to YscF, F1, and LcrV. Total RNA was extracted from peripheralblood lymphocytes isolated from the immune alpaca and used as a templatefor first strand cDNA synthesis with oligo(dT) primer. Using this cDNA,the VHH encoding sequences were amplified by PCR and cloned into thephagemid vector pHEN4. pHEN4 vectors containing the amplified VHHsequences were transformed into electrocompetent cells to obtain a VHHlibrary of about 1-2×10⁸ independent transformants. About 75-93% oftransformants harbored vectors with the correct insert sizes.Antigen-specific SAbs were then selected from a phage display library.

Example 2: Isolation of YscF SAbs

For the YscF antigen, the VHH library was subjected to four consecutiverounds of panning, performed on solid-phase coated antigen(concentration: 700 μg/ml, 30 μg/well, in 25 mM Tris (pH not tested),150 mM NaCl, 0.05% Tween-20, and 1 mM EDTA). The enrichment forantigen-specific phages after each round of panning was assessed bycomparing the number of phages eluted from antigen-coated wells with thenumber of phages eluted from negative control (only blocked) wells. Theenrichment was also evaluated by polyclonal phage ELISA, which is shownin FIG. 4. These experiments suggested that the phage population wasenriched for antigen-specific phages only after the third round ofpanning. In total, 385 individual colonies (95, 143, and 47 from second,third, and fourth rounds, respectively) were randomly selected andanalyzed by ELISA for the presence of YscF-specific SAbs in theirperiplasmic extracts. Out of these 385 colonies, 19 colonies (all fromthe third round) scored positive. Sequencing of positive coloniesidentified seven different SAbs, and the ELISA results for these sevenSAbs are shown in FIG. 5. The protein sequences of the seven exemplaryYscF SAbs according to the present invention are shown in Table 3, andthe nucleic acid sequences encoding the seven exemplary YscF SAbs areshown in Table 4.

FIG. 10 is a protein sequence alignment of the seven exemplary YscF SAbslisted in Table 3, and FIGS. 15A-C are sequence alignments of thenucleic acid sequences listed in Table 4. Gaps are introduced in thesequences contained in FIGS. 10 and 15A-C as needed in order to alignthe respective protein and nucleic acid sequences with one another.Referring to FIG. 10, the three CDRs are underlined in each sequence.The CDRs are defined according to the Kabat numbering system [Kabat, E.A., et al., (1991) Sequences of Proteins of Immunological Interest,Fifth Edition, NIH Publication No. 91-3242, US Department of Health andHuman Services, Bethesda, Md.]. The differences in the four FRs of eachSAb (if any), as compared with 3YscF57 (SEQ ID NO:154), are in bold; anydifferences between the three CDRs of each SAb are not otherwiseindicated. The seven exemplary YscF SAb sequences depicted in FIG. 10and listed in Table 3 represent seven different groups i.e. theyoriginate from seven clonally-unrelated B-cells.

Example 3: Isolation of F1 SAbs

For the F1 antigen, the library was subjected to four consecutive roundsof panning, performed on solid-phase coated antigen (concentration: 200μg/ml, 20 μg/well, in the presence of 0.005% Tween-20). The enrichmentfor antigen-specific phages after each round of panning was assessed bycomparing the number of phages eluted from antigen-coated wells with thenumber of phages eluted from negative control (blocked only) wells. Theenrichment was also evaluated by polyclonal phage ELISA, which is shownin FIG. 6. These experiments suggested that the phage population wasenriched for antigen-specific phages only after the third and fourthrounds of panning. In total, 285 individual colonies from second, third,and fourth rounds of panning (95 from each round) were randomly selectedand analyzed by ELISA for the presence of F1-specific SAbs in theirperiplasmic extracts. Out of these 285 colonies, 55 scored positive (0,29, and 26 from second, third, and fourth rounds, respectively).Sequencing of these 55 positive colonies identified 18 different SAbs,and the ELISA results for these 19 SAbs are shown in FIGS. 7A-B. Theprotein sequences of 18 exemplary F1 SAbs according to the presentinvention are shown in Table 5, and the nucleic acid sequences encodingthe 18 F1 SAbs are shown in Table 6.

FIGS. 11A-B are protein sequence alignments of the 18 exemplary F1 SAbslisted in Table 5, and FIGS. 16A-H are sequence alignments of thenucleic acid sequences listed in Table 6. Gaps are introduced in thesequences in FIGS. 11A-B and 16A-H as needed in order to align theprotein and nucleic acid sequences with one another. Referring to FIGS.11A-B, the three CDRs are underlined in each sequence. The CDRs aredefined according to the Kabat numbering system. The differences in thefour FRs of each SAb (if any), as compared with 3F55 (SEQ ID NO:168),are in bold; any differences between the three CDRs of each SAb are nototherwise indicated. The 18 exemplary F1 SAbs shown in FIGS. 11A-B andlisted in Table 5 represent 10 different groups, which are listed inTable 9. SAbs belonging to the same group are very similar, especiallyin the CDR3 region, and their amino acid sequences suggest that they areeither from clonally-related B-cells resulting from somatichypermutation or from the same B-cell with diversification due to PCRerror during library construction.

Example 4: Isolation of LcrV SAbs

For the LcrV antigen, the library was subjected to three consecutiverounds of panning, performed on solid-phase coated antigen(concentration: 200 μg/ml, 20 μg/well). The enrichment forantigen-specific phages after each round of panning was assessed bycomparing the number of phages eluted from antigen-coated wells with thenumber of phages eluted from negative control (blocked only) wells. Theenrichment was also evaluated by polyclonal phage ELISA, which is shownin FIG. 8. These experiments suggested that the phage population wasenriched for antigen-specific phages after the first, second, and thirdrounds of panning. 95 individual colonies from the second round ofpanning were randomly selected and analyzed by ELISA for the presence ofLcrV-specific SAbs in their periplasmic extracts (not shown). Out ofthese 95 colonies, 85 scored positive. The VHHs from the 85 positivecolonies were subjected to restriction fragment length polymorphism(RFLP) analysis using HinfI enzyme (not shown). Based on RFLP analysis,40 colonies (several from each RFLP group) were selected for sequencing.Sequence analysis identified four different SAbs.

The high redundancy of the LcrV positive colonies identified after thesecond round of panning, together with the fact that the enrichment forantigen-specific phages was already good after the first round ofpanning, suggested that additional rounds of panning may have led to aloss of library diversity. To address this possibility and to identifyadditional unique sequences, 95 colonies from first round of panningwere randomly selected and analyzed by ELISA for the presence ofLcrV-specific SAbs in their periplasmic extracts, which is shown inFIGS. 9A-B. Out of these 95 colonies from the first round, 35 colonieswere positive. These 35 colonies represented the four previouslyidentified SAbs, as well as 10 novel sequences. The protein sequences of14 exemplary LcrV SAbs according to the present invention are shown inTable 7, and the nucleic acid sequences encoding the 14 LcrV SAbs areshown in Table 8.

FIGS. 12A-B are the protein sequence alignment of the 14 exemplary LcrVSAbs listed in Table 7, and FIGS. 17A-F are sequence alignments of thenucleic acid sequences listed in Table 8. Gaps are introduced in thesequences in FIGS. 12A-B and 17A-F as needed in order to align theprotein and nucleic acid sequences with one another. Referring to FIGS.12A-B, the three CDRs are underlined in each sequence. The CDRs aredefined according to the Kabat numbering system. The differences in thefour FRs of each SAb (if any), as compared with 1LCRV32 (SEQ ID NO:204),are shown in bold; any differences between the three CDRs of each SAbare not otherwise indicated. The 14 exemplary LcrV SAbs shown in FIGS.12A-B and listed in Table 7 represent six different groups, which arelisted in Table 10. SAbs belonging to the same group are very similar,and their amino acid sequences suggest that they are fromclonally-related B-cells resulting from somatic hypermutation or fromthe same B-cell with diversification due to PCR error during libraryconstruction.

Example: 5 Binding Kinetics of LcrV and F1 SAbs

Binding kinetics studies were conducted on selected LcrV and F1 SAbs.LcrV and F1 protein was immobilized on the surface of a BIACORE CM5 chip(GE Healthcare Biosciences), and each SAb was allowed toassociate/dissociate with the appropriate antigen. The results of thebinding kinetics study are shown in Table 11. Binding generally rangedfrom nM to pM, with the best two SAbs (LcrV-reactive SAbs SEQ IDNOs:209, 214) binding to the target in the mid-fM range. The bindingconstants of the seven LcrV SAbs from Table 11 (SEQ ID NOs:204, 209,211, 214-217) are shown in Table 12. The K_(D) is calculated ask_(d)/k_(a) (“n. b.”=no binding).

FIGS. 13A-B are the resulting double-referenced sensorgrams (colored bySAb concentration) obtained using a BIACORE T200 sensor instrument(General Electric Healthcare, United Kingdom) for six of the seven LcrVSAbs from Tables 11 and 12 (SEQ ID NOs:204, 209, 211, 214-217). Adissociation phase of 500 seconds was used for all concentrations ofSAb. The overlaying curve fits are depicted in black, and thesensorgrams are based on a 1:1 binding model.

Of the described SAb sets, two SAbs (SEQ ID NOs:209, 214) demonstrate nodiscernible off rate (k_(d)) within the limits of THE BIACORE instrumentanalyses (see Tables 11 and 12). In a second test, LcrV was immobilizedon the surface of a BIACORE CM5 chip, and LcrV-reactive SAbs SEQ IDNOs:209 and 214 were allowed to associate/dissociate. A dissociationphase of 120 seconds was used for all concentrations of SAb except thehighest concentration, for which a 3600 second dissociation was used.FIGS. 14A-B are the double-referenced sensorgrams (colored by SAbconcentration) obtained on the BIACORE T200 sensor instrument withoverlaying curve fits (black), based on a 1:1 binding model. These dataindicate that the SAb sequences of SEQ ID NOs:209 and 214 bind to the Y.pestis LcrV protein extremely and unusually tightly. Due to the natureof these two SAbs, both could bind to the Y. pestis bacteria in a mannerthat may make infection and/or replication difficult or impossible.

The present invention includes SAbs against at least one Y. pestissurface protein or antigen and the nucleotide sequences that encode theSAbs. The Y. pestis surface protein may include YscF, F1, and/or LcrV.The present invention includes a composition comprising a single SAb ora mixture of two or more different SAbs. For compositions comprising amixture of two or more different SAbs, all of the SAbs may be against asingle Y. pestis surface protein (single-antigen), or the SAbs may beagainst different epitopes on the same Y. pestis surface protein(single-antigen, multi-epitope). The mixture of two or more differentSAbs may further comprise SAbs against two or more Y. pestis surfaceproteins (multi-antigen).

In one embodiment of the present invention, SAbs against at least one Y.pestis YscF epitope may comprise one each of a CDR1 sequence selectedfrom the group consisting of SEQ ID NOs:1-7; a CDR2 sequence selectedfrom the group consisting of SEQ ID NOs:27-33; and a CDR3 sequenceselected from the group consisting of SEQ ID NOs:54-60. In anotherembodiment, SAbs against at least one Y. pestis YscF epitope maycomprise one each of an FR1 sequence selected from the group consistingof SEQ ID NOs:79-102; a CDR1 sequence selected from the group consistingof SEQ ID NOs:1-7; an FR2 sequence selected from the group consisting ofSEQ ID NOs:103-120; a CDR2 sequence selected from the group consistingof SEQ ID NOs:27-33; an FR3 sequence selected from the group consistingof SEQ ID NOs:121-146; a CDR3 sequence selected from the groupconsisting of SEQ ID NOs:54-60; and an FR4 sequence selected from thegroup consisting of SEQ ID NOs:147-153. In a further embodiment, SAbsagainst at least one Y. pestis YscF epitope may comprise the specificarrangement of FRs and CDRs embodied in SEQ ID NOs:154-160. The presentinvention further includes isolated nucleotide sequences selected fromthe group consisting of SEQ ID NOs:161-167 that encode the SAbscomprising SEQ ID NOs:154-160.

In another embodiment, SAbs against at least one Y. pestis F1 epitopemay comprise one each of a CDR1 sequence selected from the groupconsisting of SEQ ID NOs:8-19; a CDR2 sequence selected from the groupconsisting of SEQ ID NOs:34-47; and a CDR3 sequence selected from thegroup consisting of SEQ ID NOs:61-71, AEY, and PGY. In anotherembodiment, SAbs against at least one Y. pestis F1 epitope may compriseone each of an FR1 sequence selected from the group consisting of SEQ IDNOs:79-102; a CDR1 sequence selected from the group consisting of SEQ IDNOs:8-19; an FR2 sequence selected from the group consisting of SEQ IDNOs:103-120; a CDR2 sequence selected from the group consisting of SEQID NOs:34-47; an FR3 sequence selected from the group consisting of SEQID NOs:121-146; a CDR3 sequence selected from the group consisting ofSEQ ID NOs:61-71, AEY, and PGY; and an FR4 sequence selected from thegroup consisting of SEQ ID NOs:147-153. In a further embodiment, SAbsagainst at least one Y. pestis F1 epitope comprise the specificarrangement of FRs and CDRs embodied in SEQ ID NOs:168-185. The presentinvention further includes isolated nucleotide sequences selected fromthe group consisting of SEQ ID NOs:186-203 that encode the SAbscomprising SEQ ID NOs:168-185.

In a further embodiment, SAbs against at least one Y. pestis LcrVepitope may comprise one each of a CDR1 sequence selected from the groupconsisting of SEQ ID NOs:20-26; a CDR2 sequence selected from the groupconsisting of SEQ ID NOs:48-53; and a CDR3 sequence selected from thegroup consisting of SEQ ID NOs:72-78 and GNI. In another embodiment,SAbs against at least one Y. pestis LcrV epitope may comprise one eachof an FR1 sequence selected from the group consisting of SEQ IDNOs:79-102; a CDR1 sequence selected from the group consisting of SEQ IDNOs:20-26; an FR2 sequence selected from the group consisting of SEQ IDNOs:103-120; a CDR2 sequence selected from the group consisting of SEQID NOs:48-53; an FR3 sequence selected from the group consisting of SEQID NOs:121-146; a CDR3 sequence selected from the group consisting ofSEQ ID NOs:72-78 and GNI; and an FR4 sequence selected from the groupconsisting of SEQ ID NOs:147-153. In a further embodiment, SAbs againstat least one Y. pestis LcrV epitope may comprise the specificarrangement of FRs and CDRs embodied in SEQ ID NOs:204-217. The presentinvention further includes isolated nucleotide sequences selected fromthe group consisting of SEQ ID NOs:218-231 that encode the SAbscomprising SEQ ID NOs:204-217.

In an alternative embodiment, the present invention includes one or moreSAbs against Y. pestis YscF, with each SAb comprising a CDR1 sequence, aCDR2 sequence, and a CDR3 sequence respectively having at least 15%sequence identity with a CDR1 sequence selected from the groupconsisting of SEQ ID NOs:1-7; a CDR2 sequence selected from the groupconsisting of SEQ ID NOs:27-33; and a CDR3 sequence selected from thegroup consisting of SEQ ID NOs:54-60, in which the SAbs retainsufficient affinity for at least one of a Y. pestis YscF antigen or a Y.pestis YscF epitope. The present invention further includes one or moreSAbs against Y. pestis YscF having at least 15% sequence identity withSEQ ID NOs:154-160, in which the SAbs retain sufficient affinity for atleast one of a Y. pestis YscF antigen or a Y. pestis YscF epitope.

The present invention further includes one or more SAbs against Y.pestis F1, with each SAb comprising a CDR1 sequence, a CDR2 sequence,and a CDR3 sequence respectively having at least 15% sequence identitywith at least one of a CDR1 sequence selected from the group consistingof SEQ ID NOs:8-19, a CDR2 sequence selected from the group consistingof SEQ ID NOs:34-47, and a CDR3 sequence selected from the groupconsisting of SEQ ID NOs:61-71, AEY, and PGY, in which the SAbs retainsufficient affinity for at least one of a Y. pestis F1 antigen or a Y.pestis F1 epitope. The present invention further includes one or moreSAbs against Y. pestis F1 having at least 15% sequence identity with SEQID NOs: 168-185, in which the SAbs retain sufficient affinity for atleast one of a Y. pestis F1 antigen or a Y. pestis F1 epitope

The present invention further includes one or more SAbs against Y.pestis LcrV, with each SAb comprising a CDR1 sequence, a CDR2 sequence,and a CDR3 sequence respectively having at least 15% sequence identitywith at least one of a CDR1 sequence selected from the group consistingof SEQ ID NOs:20-26, a CDR2 sequence selected from the group consistingof SEQ ID NOs:48-53, and a CDR3 sequence selected from the groupconsisting of SEQ ID NOs:72-78 and GNI, in which the SAbs retainsufficient affinity for at least one of a Y. pestis LcrV antigen or a Y.pestis LcrV epitope. The present invention further includes one or moreSAbs against Y. pestis LcrV having at least 15% sequence identity withSEQ ID NOs: 204-217, in which the SAbs retain sufficient affinity for atleast one of a Y. pestis LcrV antigen or a Y. pestis LcrV epitope.

In an another embodiment, the present invention further includes apolypeptide, which is used herein to refer to a structure comprising twoor more of any of the above-described SAbs against Y. pestis YscF, F1,and/or LcrV in which the two or more SAbs are joined together. In oneembodiment, the polypeptide may comprise a fusion protein that iscreated by joining together two or more SAbs at the genetic level. Twoor more nucleic acid sequences encoding for two or more SAbs may bespliced together, and translation of the spliced nucleic acid sequencecreates a longer, multi-antigen and/or multi-epitope fusion protein. Thefusion protein may contain up to four SAbs joined end-to-end in asubstantially linear fashion, similar to beads on a string.

In one embodiment, the fusion protein comprises SAbs that are allagainst a single Y. pestis surface protein or antigen i.e. asingle-antigen fusion protein against either YscF, F1, or LcrV. In afurther embodiment, this single-antigen fusion protein further comprisesSAbs that bind to two or more different epitopes (multi-epitope,single-antigen) on the single antigen. In another embodiment, the fusionprotein may comprise SAbs against two or more different Y. pestissurface proteins i.e. a multi-antigen fusion protein. The multi-antigenfusion protein may also comprise SAbs that bind to two or more differentepitopes (multi-epitope, multi-antigen) on the same antigen(s). In use,each individual fusion protein molecule may bind to one Y. pestissurface protein molecule, or the individual fusion protein molecule maybe bound to two or more separate Y. pestis surface protein molecules.Use of a multi-antigen and/or multi-epitope fusion protein may increaseavidity in enzyme immunosorbent assays.

In another embodiment, the polypeptide may be created by joining two ormore SAbs together with a protein or chemical linker to create amultivalent protein complex. For example, a linker molecule such as theverotoxin 1B-subunit may be used to create high avidity, pentavalent SAbcomplexes similar to keys on a key ring. In one embodiment, themultivalent protein complex may contain SAbs that are all against asingle Y. pestis surface protein or antigen i.e. a single-antigenmultivalent protein complex. This single-antigen multivalent proteincomplex may further comprise SAbs that bind to two or more differentepitopes (multi-epitope, single-antigen) on the single antigen. Inanother embodiment, the multivalent protein complex may comprise SAbsagainst two or more different Y. pestis surface proteins i.e. amulti-antigen multivalent protein complex. The multi-antigen multivalentprotein complex may further comprise SAbs that bind to two or moredifferent epitopes (multi-epitope, multi-antigen) on the same antigen.In use, each multivalent protein complex may bind to one Y. pestissurface protein molecule, or the multivalent protein complex may bebound to two or more separate Y. pestis surface protein molecules. Thesemulti-antigen and/or multi-epitope multivalent protein complexes maygenerally demonstrate increased affinity for their respective epitopeand/or antigen target(s) and may have numerous applications forbiomarker assays or proteomics.

In one embodiment of the present invention, polypeptides as describedherein comprise at least two SAbs, with the SAbs being selected from thefollowing groups: (1) SAbs comprising one each of a CDR1 sequenceselected from the group consisting of SEQ ID NOs:1-7; a CDR2 sequenceselected from the group consisting of SEQ ID NOs:27-33; and a CDR3sequence selected from the group consisting of SEQ ID NOs:54-60; (2)SAbs comprising one each of a CDR1 sequence selected from the groupconsisting of SEQ ID NOs:8-19; a CDR2 sequence selected from the groupconsisting of SEQ ID NOs:34-47; and a CDR3 sequence selected from thegroup consisting of SEQ ID NOs:61-71, AEY, and PGY; and (3) SAbscomprising one each of a CDR1 sequence selected from the groupconsisting of SEQ ID NOs:20-26; a CDR2 sequence selected from the groupconsisting of SEQ ID NOs:48-53; and a CDR3 sequence selected from thegroup consisting of SEQ ID NOs:72-78 and GNI.

In a further embodiment, the polypeptides comprise at least two SAbsselected from the group consisting of: (1) SAbs comprising one each of aCDR1 sequence selected from the group consisting of sequences having atleast 15% sequence identity with SEQ ID NOs:1-7; a CDR2 sequenceselected from the group consisting of sequences having at least 15%sequence identity with SEQ ID NOs: 27-33; and a CDR3 sequence selectedfrom the group consisting of sequences having at least 15% sequenceidentity with SEQ ID NOs:54-60; (2) SAbs comprising one each of a CDR1sequence selected from the group consisting of sequences having at least15% sequence identity with SEQ ID NOs: 8-19; a CDR2 sequence selectedfrom the group consisting of sequences having at least 15% sequenceidentity with SEQ ID NOs: 34-47; and a CDR3 sequence selected from thegroup consisting of sequences having at least 15% sequence identity withSEQ ID NOs: 61-71; and (3) SAbs comprising one each of a CDR1 sequenceselected from the group consisting of sequences having at least 15%sequence identity with SEQ ID NOs: 20-26; a CDR2 sequence selected fromthe group consisting of sequences having at least 15% sequence identitywith SEQ ID NOs: 48-53; and a CDR3 sequence selected from the groupconsisting of sequences having at least 15% sequence identity with SEQID NOs: 72-78.

In another embodiment, the polypeptides may comprise at least two SAbs,with the SAbs being selected from the following groups: (1) SAbscomprising one set of CDR1, CDR2, and CDR3 sequences (as described abovewith respect to polypeptides according to the present invention) and oneeach of an FR1 sequence selected from the group consisting of SEQ IDNOs:79-102, an FR2 sequence selected from the group consisting of SEQ IDNOs:103-120, an FR3 sequence selected from the group consisting of SEQID NOs:121-146, and an FR4 sequence selected from the group consistingof SEQ ID NOs:147-153; and (2) SAbs selected from the group consistingof SEQ ID NOs:154-160, 168-185, and 204-217 and sequences having atleast 15% sequence identity with SEQ ID NOs:154-160, 168-185, and204-217.

In another embodiment, any of the SAbs or polypeptides according to thepresent invention may further comprise a protein tag, a protein domaintag, or a chemical tag. These tags generally comprise one or moreadditional amino acids or chemical molecules or residues that may beplaced using known methods on the C- or N-terminus of the SAb orpolypeptide without altering the activity or functionality of the SAb orpolypeptide. The tag may facilitate purification of the SAb orpolypeptide, direct absorption and/or excretion in the body, and/orfacilitate use in a variety of applications such as detecting andmonitoring Y pestis. The tag may include, but is not limited to, ahistidine tag (HIS tag) and a poly-lysine tag.

The present invention further includes a method of preventing ortreating a Y. pestis infection in a patient. Y. pestis infections arefrequently difficult to properly diagnose, which can result in delayedtreatment, and a low toxicity treatment such as the presently disclosedSAbs may provide a valuable tool for cases of suspected Y. pestisexposure and/or infection and/or for patients presenting with ambiguoussymptoms. The method comprises identifying a patient who is suspected ofhaving been exposed to and/or infected with Y. pestis, and administeringto the patient a pharmaceutically active amount of one or more of theSAbs and/or polypeptides according to the present invention. As usedthroughout, a “pharmaceutically active amount” refers generally to anamount that upon administration to the patient, is capable of providingdirectly or indirectly, one or more of the effects or activitiesdisclosed herein. In one embodiment, the SAb(s) and/or polypeptide(s)may be administered as a form of passive immunotherapy in which theSAb(s) and/or polypeptide(s) are administered to the patient prior to atleast one of exposure to or infection with Y. pestis. In anotherembodiment, the SAb(s) and/or polypeptide(s) may be administered afterthe patient is exposed to or infected with Y. pestis. The SAb(s) and/orpolypeptide(s). In all embodiments of the methods, the SAb(s) and/orpolypeptide(s) may be capable of being self-administered and may beadministered to the patient using known techniques including, but notlimited to, intravenous and subcutaneous injection, oral ingestion,inhalation, and topical administration. The ability to self-administerthe SAb(s) and/or polypeptide(s) may be particularly useful in the caseof an outbreak or attack where access to medical personnel and treatmentmay be limited.

The present invention further includes a method of detecting and/ordiagnosing a Y. pestis infection using one of more of the SAbs and/orpolypeptides herein described. The method may include detection of Y.pestis and diagnosis of the infection using known in vivo and/or invitro assays such as enzyme linked immunosorbent assays (ELISAs), dotblot assays, and other suitable immunoassays. The Y. pestis SAb(s)and/or polypeptide(s) may, for example, be used as a primary antibody ora capture antibody in an ELISA for the detection/diagnosis of a Y.pestis infection. The SAb(s) and/or polypeptide(s) according to thepresent invention may further be coupled to one or more enzymes ormarkers for use in imaging.

The present invention further includes devices and methods for theidentification and detection of Y. pestis on a surface and/or in anenvironment. A device for the environmental detection and/orquantification of Y. pestis may comprise one or more of the SAbs orpolypeptides according to the present invention, with the SAb(s) and/orpolypeptide(s) being used as a capture element. A method of identifyingand detecting Y. pestis using the device comprises contacting one ormore of the SAbs or polypeptides with an unknown target and detectingbinding between the SAbs or polypeptides and the unknown target toidentify the unknown target as Y. pestis. The method may furthercomprise use of the device to quantify an amount of Y. pestis on thesurface and/or in the environment.

TABLE 1 Amino Acid Code Alanine Ala A Methionine Met M Cysteine Cys CAsparagine Asn N Aspartic Acid Asp D Proline Pro P Glutamic Acid Glu EGlutamine Gln Q Phenylalanine Phe F Arginine Arg R Glycine Gly G SerineSer S Histidine His H Threonine Thr T Isoleucine Ile I Valine Val VLysine Lys K Tryptophan Trp W Leucine Leu L Tyrosine Tyr Y

TABLE 2 Exemplary Combinations of FR and CDR Sequences ID ID ID ID ID IDID # FR1 # CDR1 # FR2 # CDR2 # FR3 # CDR3 # FR4 YscF SAb Sequences  79QVQLQESGG  1 GRTWR 103 WFRQ 27 VMSRSG 121 RFTISRDNAKN 54 GGGMY 147WGKGTQ GLVQAGGSL AYYMG APGKE GTTSYA TVYLQMNNLA GPDLYG VTVSS RLSCAASREFVA DSVKG PEDTATYYCK MTY A  80 QVQLQESGG  2 GRAFS 103 WFRQ 28 ANWRSG122 RFTISRDDAKN 55 GGGSRW 148 WGQGTQ GLVQAGGSL NYAMA APGKE GLTDYATVYLQMNSLK YGRTTA VTVSS RLSCVAS REFVA DSVKG PEDTAVYYCA SWYDY A  81QVQLQESGG  3 GRTFSR 103 WFRQ 29 AISWSGS 123 RFTISRDHAKN 56 PAYGLR 149RGQGTQ GLVQAGGSL YAMG APGKE STYYAD VMYLQMNGL PPYNY VTVSS RLSCAVS REFVASVKG KPEDTGVYVC AR  82 QVQLQESGG  4 QRTFSR 104 WFRQ 30 ATTWSG 124RFTISRDNAKN 57 GRSSWF 150 WGRGTQ GLVQAGGSL YSLG APGEE ISSDYAD TGYLQMNNLKAPWLTP VTVSS KLSCTAS RVFVA SVKG PEDTGVYYCA YEYDY A  79 QVQLQESGG  5GRTFSS 105 WFRQ 31 AIRWNG 125 RFTISRDLAKN 58 GVYDY 148 WGQGTQ GLVQAGGSLHAMA GPGEE DNIHYS TLYLQMNSLK VTVSS RLSCAAS RQFLA DSAKG PEDTAVYYCA R  83QVQLQESGG  6 GRTFG 106 WFRRA 32 GITRSGN 126 RFTISRDNAKN 59 DWGWR 148WGQGTQ GLVQAGDSR RPFRYT PGKER NIYYSDS TVYLQMNSLK NY VTVSS ILSCTAS MGEFVG VKG PEDTAVYYCN A  84 QVQLQESGG  7 GETVD 107 WFRQA 33 CISGSDG 127RFTISRDNVKN 60 EIYDRR 148 WGQGTQ GLVQAGGSL DLAIG PGKER STYYAD TVYLQMNSLKWYRND VTVSS RLACAAS EEIS SLSG LEDTAVYYCY Y A F1 SAb Sequences  81QVQLQESGG  8 GMMYI 108 WYRQA 34 FVSSTGN 128 RFTISRDNAKN 61 YLGSRD 148WGQGTQ GLVQAGGSL REAIR PGKQR PRYTDS TVYLQMNSLTP Y VTVSS RLSCAVS EWVA VKGEDTAVYYCNT  85 QVQLQESGG  9 GMMYI 108 WYRQA 35 VVSSTG 128 RFTISRDNAKN 61YLGSRD 148 WGQGTQ GLVQPGGSL RYTMR PGKQR NPHYAD TVYLQMNSLTP Y VTVSSRLSCAVS EWVA SVKG EDTAVYYCNT  86 QVQLQESGG 10 GRAVN 109 WYRQA 36 FISVGGT129 RFTVSRDNAKN * AEY 148 WGQGTQ GLVRPGGSL RYHIMH PGKQR TNYAGSTLYLQMNSLKP VTVSS RLSCAVS EWVT VKG EDTAVYYCNS  87 QVQLQESGG 11 GIIFSD108 WYRQA 37 QITRSQN 130 RFTVSRDNAKN 62 YDGRRP 148 WGQGTQ GSVQPGGSL YALTPGKQR INYTGSV TVHLQMNSLK PY VTVSS SLSCSAS EWVA KG PEDTAVYYCH A  87QVQLQESGG 11 GIIFSD 108 WYRQA 37 QITRSQN 130 RFTVSRDNAKN 63 YDGRRR 148WGQGTQ GSVQPGGSL YALT PGKQR INYTGSV TVHLQMNSLK TY VTVSS SLSCSAS EWVA KGPEDTAVYYCH A  88 QVQLQESGG 11 GIIFSD 108 WYRQA 37 QITRSQN 130RFTVSRDNAKN 62 YDGRRP 148 WGQGTQ GLVQPGGSL YALT PGKQR INYTGSV TVHLQMNSLKPY VTVSS SLSCSAS EWVA KG PEDTAVYYCH A  88 QVQLQESGG 11 GIIFSD 108 WYRQA38 QITRRQ 130 RFTVSRDNAKN 64 YDGRRS 148 WGQGTQ GLVQPGGSL YALT PGKQRNINYTG TVHLQMNSLK PY VTVSS SLSCSAS EWVA SVKG PEDTAVYYCH A  89 QVQLQESGG11 GIIFSD 108 WYRQA 37 QITRSQN 131 RFTVSRDNAKN 62 YDGRRP 148 WGQGTQGLVQPGGSL YALT PGKQR INYTGSV TVHLQMNSLKP PY VTVSS RLSCSAS EWVA KGEDAAVYYCHA  90 QVQLQESGG 12 ARIFSI 108 WYRQA 39 AITTGGT 126RFTISRDNAKN * PGY 148 WGQGTQ GLVQPGGSL YAMV PGKQR TNYADS TVYLQMNSLKVTVSS RLSCAAS EWVA VKG PEDTAVYYCN A  90 QVQLQESGG 13 GVIASI 110 WYRQT 40IITSGGN 132 RFTTSRDNARN 65 LVGAKD 148 WGQGTQ GLVQPGGSL SVLR PGKTR TRYADSTVYLQMNSLKP Y VTVSS RLSCAAS DWVA VKG EDTAVYYCNT  91 QVQLQESGG 14 GTTFRS111 WYRQA 41 FISSPGD 133 RFTISRDNAKN 66 NGIY 147 WGKGTQ GLVRPGGSL LVMKPGKER RTRYTE ALYLQMNGLK VTVSS RLSCEAS EWVA AVKG PEDTAVYYCN A  92QVQLQESGG 15 GFTFSN 112 WVRQA 42 TINSGG 134 RFTISRDNAKN 67 TASHIP 151LSQGTQ GLVQSGDSL YAMS PGKGL GSTSYA TLYLQMNSLKP VTVSS RLSCAAS EWVS YSVKGEDTAVYYCAK  90 QVQLQESGG 15 GFTFSN 112 WVRQA 43 TINIGGG 134 RFTISRDNAKN67 TASHIP 151 LSQGTQ GLVQPGGSL YAMS PGKGL STSYAD TLYLQMNSLKP VTVSSRLSCAAS EWVS SVKG EDTAVYYCAK  90 QVQLQESGG 16 GFTFRN 112 WVRQA 44 TINGGG135 RFTISRDNAKN 68 TARDSR 149 RGQGTQ GLVQPGGSL YAMS PGKGL GITSYADTMYLQMNSLK DS VTVSS RLSCAAS EWVS SVKG PEDTAVYYCA Q  90 QVQLQESGG 17GFTFSS 113 WVRLA 45 TINIAGG 134 RFTISRDNAKN 69 TAANWS 149 RGQGTQGLVQPGGSL YAMS PGKGL ITSYADS TLYLQMNSLKP AQ VTVSS RLSCAAS EWVS VKGEDTAVYYCAK  90 QVQLQESGG 17 GFTFSS 112 WVRQA 46 TINMGG 136 RFTISRHNAKN70 TAGNWS 149 RGQGTQ GLVQPGGSL YAMS PGKGL GTTSYA  TLYLQMNSLKP AQ VTVSSRLSCAAS EWVS DSVKG EDTAVYYCAK  90 QVQLQESGG 18 GFTFST 114 WIRQPP 47TITSAGG 137 RFTISRDNAKN 71 LVNLAQ 152 TGQGTQ GLVQPGGSL SAMS GKARESISYVNS TLYLQMNMLK VTVSS RLSCAAS VVA VKG PEDTAVYYCAR  90 QVQLQESGG 19GFTFST 114 WIRQPP 47 TITSAGG 137 RFTISRDNAKN 71 LVNLAQ 152 TGQGTQGLVQPGGSL NAMS GKARE SISYVNS TLYLQMNMLK VTVSS RLSCAAS VVA VKGPEDTAVYYCAR LcrV SAb Sequences  93 QVQLQESGG 20 GFRFSS 115 WVRQA 48AINSDG 138 RFTISRDNARN 72 RDLYCS 149 RGQGTQ GMVEPGGSL YAMS PGKGL DKTSYATLYLQMSNLKP GSMCKD VTVSS RLSCAAS ERVS DSVKG EDTAVYYCAD VLGGAR YDF  94QVQLQESGG 20 GFRFSS 115 WVRQA 48 AINSDG 138 RFTISRDNARN 72 RDLYCS 149RGQGTQ GLVEPGGSL YAMS PGKGL DKTSYA TLYLQMSNLKP GSMCKD VTVSS RLSCAAS ERVSDSVKG EDTAVYYCAD VLGGAR YDF  93 QVQLQESGG 20 GFRFSS 115 WVRQA 48 AINSDG139 RFTISRDNARN 72 RDLYCS 149 RGQGTQ GMVEPGGSL YAMS PGKGL DKTSYATLYLQMNNLK GSMCKD VTVSS RLSCAAS ERVS DSVKG PEDTAVYYCA VLGGAR D YDF  95QVQLQESGG 21 GLRFSS 115 WVRQA 48 AINSDG 138 RFTISRDNARN 72 RDLYCS 149RGQGTQ GLVQSGESL YAMS PGKGL DKTSYA TLYLQMSNLKP GSMCKD VTVSS RLSCAAS ERVSDSVKG EDTAVYYCAD VLGGAR YDF  96 QVQLQESGG 22 GFTFN 116 WYRQV 49 TITGASG140 RFTISRDNAKN 73 YLTYDS 148 WGQGTQ GLVQPGGSL WYTM PGEER DTKYADTVTLQMNSLKP GSVKGV VTVSS KLSCAAS A KMVA SVKG GDAAVYYCHA NY  97 QVQLQESGG22 GFTFN 116 WYRQV 49 TITGASG 141 RFTISRDNAKN 73 YLTYDS 148 WGQGTQGLVRPGGSL WYTM PGEER DTKYAD TVTLQMNSLKP GSVKGV VTVSS KLSCAAS A KMVA SVKGGDTAVYYCHA NY  98 QVQLQESGG 22 GFTFN 116 WYRQV 49 TITGASG 141RFTISRDNAKN 73 YLTYDS 148 WGQGTQ GSVQPGGSL WYTM PGEER DTKYAD TVTLQMNSLKPGSVKGV VTVSS KLSCAAS A KMVA SVKG GDTAVYYCHA NY  98 QVQLQESGG 22 GFTFN116 WYRQV 49 TITGASG 141 RFTISRDNAKN 74 CLTYDS 148 WGQGTQ GSVQPGGSL WYTMPGEER DTKYAD TVTLQMNSLKP GSVKGV VTVSS KLSCAAS A KMVA SVKG GDTAVYYCHA NY 99 QVQLQESGG 22 GFTFN 116 WYRQV 49 TITGASG 141 RFTISRDNAKN 73 YLTYDS148 WGQGTQ GFVQPGGSL WYTM PGEER DTKYAD TVTLQMNSLKP GSVKGV VTVSS KLSCAASA KMVA SVKG GDTAVYYCHA NY  96 QVQLQESGG 22 GFTFN 116 WYRQV 49 TITGASG141 RFTISRDNAKN 75 YLTYDS 148 WGQGTQ GLVQPGGSL WYTM PGEER DTKYADTVTLQMNSLKP GSAKGV VTVSS KLSCAAS A KMVA SVKG GDTAVYYCHA NY 100 QVQLQESGG23 GSLLNI 117 WYRQA 50 TVTSSG 143 RFTISRDNAKN 76 HLRYGD 148 WGQGTQGLVQPGGSL YAMG PGRQR TAEYAD TVYLQMNSLRP YVRGPP VTVSS GLSCAAS ELVA SVKGEDTGVYYCNA EYNY 90 QVQLQESGG 24 GGTLG 118 WFRQA 51 CITSSDT 144RFTISRDNAKN 77 GYYFRD 147 WGKGTQ GLVQPGGSL YYAIG PGKER SAYYAD TMYLQMNNLKYSDSYY VTVSS RLSCAAS EAVS SAKG PEDTAVYYCA YTGTGM A KV 101 QVQLQESGG 25GFTLDI 119 WFRQA 52 WIVGND 145 RFTISRDNAKN 78 YSGRPP 148 WGQGTQGLVQPGGST YAIG PGKEH GRTYYI TVYLEMNSLKP VGRDGY VTVSS RLSCAAS EGVS DSVKGEDTAVYYCAA DY 102 QVQLQESGG 26 GASLR 120 WSRQG 53 VMAPDY 146RVAVRGDVVK * GNI 153 RGLGTQ GLVQPGGSL DRRVT PGKSLE GVHYFG NTVYLQVNALVTVSS ILSCTIS IIA KPEDTAIYWCS M *These sequences have fewer than therequired minimum of four amino acids and are not assigned a SEQ. NO.? 

TABLE 3 Y. pestis YscF SAb Protein Sequences SEQ ID NO Name Sequence 1543yscf57QVQLQESGGGLVQAGGSLRLSCAASGRTWRAYYMGWFRQAPGKEREFVAVMSRSGGTTSYADSVKGRFTISRDNAKNTVYLQMNNLAPEDTATYYCKAGGGMYGPDLYGMTYWGKGTQVTVSS 155 3yscf124QVQLQESGGGLVQAGGSLRLSCVASGRAFSNYAMAWFRQAPGKEREFVAANWRSGGLTDYADSVKGRFTISRDDAKNTVYLQMNSLKPEDTAVYYCAAGGGSRWYGRTTASWYDYWGQGTQVTVSS 1563yscf15QVQLQESGGGLVQAGGSLRLSCAVSGRTFSRYAMGWFRQAPGKEREFVAAISWSGSSTYYADSVKGRFTISRDHAKNVMYLQMNGLKPEDTGVYVCARPAYGLRPPYNYRGQGTQVTVSS 157 3yscf24QVQLQESGGGLVQAGGSLKLSCTASQRTFSRYSLGWFRQAPGEERVFVAATTWSGISSDYADSVKGRFTISRDNAKNTGYLQMNNLKPEDTGVYYCAAGRSSWFAPWLTPYEYDYWGRGTQVTVSS 1583yscf142QVQLQESGGGLVQAGGSLRLSCAASGRTFSSHAMAWFRQGPGEERQFLAAIRWNGDNIHYSDSAKGRFTISRDLAKNTLYLQMNSLKPEDTAVYYCARGVYDYWGQGTQVTVSS 159 3yscf75QVQLQESGGGLVQAGDSRILSCTASGRTFGRPFRYTMGWFRRAPGKEREFVGGITRSGNNIYYSDSVKGRFTISRDNAKNTVYLQMNSLKPEDTAVYYCNADWGWRNYWGQGTQVTVSS 160 3yscf140QVQLQESGGGLVQAGGSLRLACAASGETVDDLAIGWFRQAPGKEREEISCISGSDGSTYYADSLSGRFTISRDNVKNTVYLQMNSLKLEDTAVYYCYAEIYDRRWYRNDYWGQGTQVTVSS

TABLE 4 Y. pestis YscF SAb DNA Sequences SEQ ID NO Name Sequence 1613yscf57 CAGGTGCAGCTGCAGGAGTCTGGGGGAGGATTGGTGCAGGCTGGGGGCTCTCTGAGACTCTCCTGTGCAGCCTCTGGACGCACCTGGAGAGCCTATTACATGGGCTGGTTCCGCCAGGCTCCAGGGAAGGAGCGTGAGTTTGTAGCAGTTATGAGTCGGAGCGGTGGCACCACATCCTATGCGGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGGTGTATCTACAAATGAACAACCTGGCACCTGAGGACACGGCCACGTATTATTGTAAGGCGGGGGGCGGAATGTACGGGCCGGACCTGTATGGTATGACATACTGGGGCAAAGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 162 3yscf124CAGGTGCAGCTGCAGGAGTCTGGAGGAGGATTGGTACAGGCTGGGGGCTCTCTGAGACTCTCCTGTGTAGCCTCTGGACGCGCCTTCAGTAATTATGCGATGGCCTGGTTCCGCCAGGCTCCAGGGAAGGAGCGTGAGTTTGTAGCAGCTAATTGGCGGAGTGGTGGTCTTACAGACTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACGACGCCAAGAACACGGTGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTTTATTACTGTGCCGCCGGGGGCGGTAGTCGCTGGTACGGGCGAACAACCGCAAGTTGGTATGACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 163 3yscf15CAGGTGCAGCTGCAGGAGTCTGGGGGAGGATTGGTGCAGGCTGGGGGCTCTCTGAGACTCTCCTGTGCAGTCTCTGGACGCACCTTCAGTAGATATGCCATGGGCTGGTTCCGCCAGGCTCCAGGGAAGGAGCGTGAGTTTGTAGCAGCTATTAGCTGGAGTGGTAGTAGCACATATTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACCACGCCAAGAACGTGATGTATCTGCAAATGAACGGCCTGAAACCTGAGGACACGGGTGTTTATGTCTGTGCAAGACCAGCGTACGGACTCCGCCCCCCGTATAATTACCGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 164 3yscf24CAGGTGCAGCTGCAGGAGTCTGGGGGAGGATTGGTGCAGGCTGGGGGCTCTCTGAAACTCTCCTGCACAGCCTCTCAACGCACCTTCAGTCGCTATAGCTTGGGCTGGTTCCGCCAGGCTCCAGGTGAGGAGCGTGTTTTTGTAGCCGCTACTACATGGAGTGGTATAAGCAGTGACTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGGGGTATCTGCAAATGAACAATTTAAAACCTGAGGACACGGGCGTTTATTACTGTGCAGCAGGACGTAGTAGCTGGTTCGCCCCCTGGTTGACCCCCTATGAGTATGATTATTGGGGCCGGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 165 3yscf142CAGGTGCAGCTGCAGGAGTCTGGGGGAGGATTGGTGCAGGCTGGGGGCTCTCTGAGACTCTCCTGTGCAGCCTCTGGACGCACCTTCAGTAGCCATGCCATGGCCTGGTTCCGCCAGGGTCCAGGAGAGGAGCGTCAGTTTCTAGCAGCTATTAGATGGAATGGTGATAACATACACTATTCAGACTCCGCGAAGGGCCGATTCACCATCTCCAGAGACCTCGCCAAGAACACGCTCTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTGTATTACTGTGCAAGGGGGGTGTATGACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGC ATAG166 3yscf75CAGGTGCAGCTGCAGGAGTCTGGGGGAGGATTGGTGCAGGCTGGGGACTCTCGGATACTCTCCTGTACAGCCTCTGGACGCACCTTTGGACGCCCCTTCAGATATACCATGGGCTGGTTCCGCCGGGCTCCAGGGAAGGAGCGTGAGTTTGTAGGAGGTATTACAAGAAGTGGTAATAATATATACTATTCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGGTGTATCTCCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTGTATTATTGTAACGCAGATTGGGGGTGGAGGAACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 167 3yscf140CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGGCTGGGGGGTCTCTGAGACTCGCCTGTGCAGCCTCTGGAGAGACTGTCGATGATCTTGCCATCGGCTGGTTCCGCCAGGCCCCAGGGAAGGAGCGTGAGGAGATTTCATGTATTAGTGGTAGTGATGGTAGCACATACTATGCAGACTCCCTGTCGGGCCGATTCACCATCTCCAGGGACAACGTCAAGAACACGGTGTATCTGCAAATGAACAGCCTGAAACTTGAGGACACGGCCGTCTATTACTGTTATGCAGAGATTTACGATAGACGCTGGTATCGGAACGACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG

TABLE 5 Y. pestis F1 SAb Protein Sequences SEQ ID NO Name Sequence 1683F55 QVQLQESGGGLVQAGGSLRLSCAVSGMMYIREAIRWYRQAPGKQREWVAFVSSTGNPRYTDSVKGRFTISRDNAKNTVYLQMNSLTPEDTAVYYCNTYLGSRDYWGQGTQVTVSS 169 3F85QVQLQESGGGLVQPGGSLRLSCAVSGMMYIRYTMRWYRQAPGKQREWVAVVSSTGNPHYADSVKGRFTISRDNAKNTVYLQMNSLTPEDTAVYYCNTYLGSRDYWGQGTQVTVSS 170 3F44QVQLQESGGGLVRPGGSLRLSCAVSGRAVNRYHMHWYRQAPGKQREWVTFISVGGTTNYAGSVKGRFTVSRDNAKNTLYLQMNSLKPEDTAVYYCNSAEYWGQGTQVTVSS 171 4H4QVQLQESGGGSVQPGGSLSLSCSASGIIFSDYALTWYRQAPGKQREWVAQITRSQNINYTGSVKGRFTVSRDNAKNTVHLQMNSLKPEDTAVYYCHAYDGRRPPYWGQGTQVTVSS 172 4F6QVQLQESGGGSVQPGGSLSLSCSASGIIFSDYALTWYRQAPGKQREWVAQITRSQNINYTGSVKGRFTVSRDNAKNTVHLQMNSLKPEDTAVYYCHAYDGRRRTYWGQGTQVTVSS 173 4F1QVQLQESGGGLVQPGGSLSLSCSASGIIFSDYALTWYRQAPGKQREWVAQITRSQNINYTGSVKGRFTVSRDNAKNTVHLQMNSLKPEDTAVYYCHAYDGRRPPYWGQGTQVTVSS 174 3H1QVQLQESGGGLVQPGGSLSLScSASGIIFSDYALTWYRQAPGKQREWVAQITRRQNINYTGSVKGRFTVSRDNAKNTVHLQMNSLKPEDTAVYYCHAYDGRRSPYWGQGTQVTVSS 175 3F61QVQLQESGGGLVQPGGSLRLSCSASGIIFSDYALTWYRQAPGKQREWVAQITRSQNINYTGSVKGRFTVSRDNAKNTVHLQMNSLKPEDAAVYYCHAYDGRRPPYWGQGTQVTVSS 176 4F27QVQLQESGGGLVQPGGSLRLSCAASARIFSIYAMVWYRQAPGKQREWVAAITTGGTTNYADSVKGRFTISRDNAKNTVYLQMNSLKPEDTAVYYCNAPGYWGQGTQVTVSS 177 3F26QVQLQESGGGLVQPGGSLRLSCAASGVIASISVLRWYRQTPGKTRDWVAIITSGGNTRYADSVKGRFTTSRDNARNTVYLQMNSLKPEDTAVYYCNTLVGAKDYWGQGTQVTVSS 178 4F59QVQLQESGGGLVRPGGSLRLSCEASGTTFRSLVMKWYRQAPGKEREWVAFISSPGDRTRYTEAVKGRFTISRDNAKNALYLQMNGLKPEDTAVYYCNANGIYWGKGTQVTVSS 179 3F5QVQLQESGGGLVQSGDSLRLSCAASGFTFSNYAMSWVRQAPGKGLEWVSTINSGGGSTSYAYSVKGRFTISRDNAKNTLYLQMNSLKPEDTAVYYCAKTASHIPLSQGTQVTVSS 180 4F57QVQLQESGGGLVQPGGSLRLSCAASGFTFSNYAMSWVRQAPGKGLEWVSTINIGGGSTSYADSVKGRFTISRDNAKNTLYLQMNSLKPEDTAVYYCAKTASHIPLSQGTQVTVSS 181 4F75QVQLQESGGGLVQPGGSLRLSCAASGFTFRNYAMSWVRQAPGKGLEWVSTINGGGGITSYADSVKGRFTISRDNAKNTMYLQMNSLKPEDTAVYYCAQTARDSRDSRGQGTQVTVSS 182 3F59QVQLQESGGGLVQPGGSLRLSCAASGFTFSSYAMSWVRLAPGKGLEWVSTINIAGGITSYADSVKGRFTISRDNAKNTLYLQMNSLKPEDTAVYYCAKTAANWSAQRGQGTQVTVSS 183 4F78QVQLQESGGGLVQPGGSLRLSCAASGFTFSSYAMSWVRQAPGKGLEWVSTINMGGGTTSYADSVKGRFTISRHNAKNTLYLQMNSLKPEDTAVYYCAKTAGNWSAQRGQGTQVTVSS 184 3F1QVQLQESGGGLVQPGGSLRLSCAASGFTFSTSAMSWIRQPPGKAREVVATITSAGGSISYVNSVKGRFTISRDNAKNTLYLQMNMLKPEDTAVYYCARLVNLAQTGQGTQVTVSS 185 3F65QVQLQESGGGLVQPGGSLRLSCAASGFTFSTNAMSWIRQPPGKAREVVATITSAGGSISYVNSVKGRFTISRDNAKNTLYLQMNMLKPEDTAVYYCARLVNLAQTGQGTQVTVSS

TABLE 6 Y. pestis F1 SAb DNA Sequences SEQ ID NO Name Sequence 186 3F55CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGGCTGGGGGCTCTCTGAGACTCTCCTGTGCAGTTTCTGGAATGATGTACATTAGGGAGGCTATACGCTGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTCGCCTTTGTAAGTAGTACTGGTAATCCACGCTATACAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGGTGTATCTGCAAATGAACAGCCTGACACCTGAGGACACGGCCGTCTATTACTGTAATACATACTTGGGCTCGAGGGACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 187 3F85CAGGTGCAGCTGCAGGAGTCTGGAGGAGGCTTGGTGCAGCCTGGGGGGTCTCTGAGACTCTCCTGTGCAGTTTCTGGAATGATGTACATTAGGTACACTATGCGCTGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTCGCCGTTGTAAGTAGTACTGGTAATCCACACTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGGTGTATCTGCAAATGAACAGCCTGACACCTGAGGACACGGCCGTCTATTACTGTAATACATACTTGGGCTCGAGGGACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 188 3F44CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCGGCCTGGGGGGTCTCTGAGACTCTCCTGTGCAGTCTCTGGAAGAGCCGTCAATAGGTATCACATGCACTGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTCACATTTATTAGTGTTGGTGGTACCACAAACTATGCAGGCTCCGTGAAGGGCCGATTCACCGTCTCCCGAGACAACGCCAAAAACACGCTGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTCTATTACTGTAATTCAGCTGAATACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 189 4F34CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTCGGTGCAGCCTGGGGGGTCTCTGAGCCTCTCCTGTTCAGCCTCTGGAATCATCTTCAGTGACTATGCCCTGACCTGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTTGCACAGATTACGCGAAGTCAAAATATAAATTATACAGGATCCGTGAAGGGCCGATTCACCGTCTCCAGAGACAACGCCAAGAACACAGTGCATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTCTACTATTGTCATGCATATGACGGTCGACGCCCACCCTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 190 4F6CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTCGGTGCAGCCTGGGGGGTCTCTGAGCCTCTCCTGTTCAGCCTCTGGAATCATCTTCAGTGACTATGCCCTGACCTGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTTGCACAGATTACGCGAAGCCAAAATATAAATTATACAGGATCCGTGAAGGGCCGATTCACCGTCTCCAGAGACAACGCCAAGAACACAGTGCATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTCTACTATTGTCATGCATATGACGGTCGACGCCGAACCTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 191 4F1CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGGGGGTCTCTGAGCCTCTCCTGTTCAGCCTCTGGAATCATCTTCAGTGACTATGCCCTGACCTGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTTGCACAGATTACGCGAAGCCAAAATATAAATTATACAGGATCCGTGAAGGGCCGATTCACCGTCTCCAGAGACAACGCCAAGAACACAGTGCATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTCTACTATTGTCATGCATATGACGGTCGACGCCCACCCTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 192 3F31CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGGGGGTCTCTGAGCCTCTCCTGTTCAGCCTCTGGAATCATCTTCAGTGACTATGCCCTGACCTGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTTGCACAGATTACGCGAAGGCAAAATATAAATTATACAGGATCCGTGAAGGGCCGATTCACCGTCTCCAGAGACAACGCCAAGAACACAGTGCATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTCTACTATTGTCATGCATATGACGGTCGACGATCACCCTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 193 3F61CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGGGGGTCTCTGAGACTCTCCTGTTCAGCCTCTGGAATCATCTTCAGTGACTATGCCCTGACCTGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTTGCACAGATTACGCGAAGTCAAAATATAAATTATACAGGATCCGTGAAGGGCCGATTCACCGTCTCCAGAGACAACGCCAAGAACACAGTGCATCTGCAAATGAACAGCCTGAAACCTGAGGACGCGGCCGTCTACTATTGTCATGCATATGACGGTCGACGCCCACCCTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 194 4F27CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGGGGGTCTCTGAGACTCTCCTGTGCAGCCTCTGCCCGCATCTTCAGTATCTATGCCATGGTATGGTACCGCCAGGCTCCAGGGAAGCAGCGCGAGTGGGTCGCAGCTATTACTACTGGTGGTACCACAAACTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGGTGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTCTATTACTGTAATGCTCCGGGCTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 195 3F26CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGGGGGTCTCTGAGACTCTCCTGTGCAGCCTCTGGAGTCATCGCCAGTATCTCCGTCCTGCGCTGGTACCGCCAAACACCAGGAAAGACGCGCGACTGGGTCGCAATTATTACTAGTGGTGGCAACACACGCTATGCAGACTCCGTGAAGGGCCGATTCACCACCTCCAGAGATAACGCCAGGAACACGGTGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTCTATTACTGTAATACACTTGTAGGAGCCAAGGACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 196 4F59CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCGGCCTGGGGGATCTCTAAGACTCTCCTGTGAAGCCTCTGGAACCACCTTCAGAAGCCTCGTAATGAAATGGTACCGCCAGGCTCCAGGGAAGGAGCGCGAGTGGGTCGCATTTATTTCTAGTCCTGGTGATCGCACTCGCTACACAGAAGCCGTGAAGGGCCGATTCACCATCTCCAGAGACAATGCCAAGAACGCGCTGTATCTGCAAATGAACGGCCTGAAACCTGAGGACACGGCCGTGTATTATTGTAACGCGAACGGAATATACTGGGGCAAAGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATA G 1973F5 CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAATCTGGGGATTCTCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTCAGTAACTATGCTATGAGCTGGGTCCGCCAGGCTCCAGGAAAGGGGCTCGAGTGGGTCTCAACTATTAATAGTGGTGGTGGTAGCACAAGCTATGCGTACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTGTATTACTGTGCAAAGACGGCCTCTCACATACCCTTGAGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAG CATAG198 4F57CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAACCTGGGGGTTCTCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTCAGTAACTATGCTATGAGCTGGGTCCGCCAGGCTCCAGGAAAGGGGCTCGAGTGGGTCTCAACTATTAATATTGGTGGTGGTAGCACAAGCTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTGTATTACTGTGCAAAGACGGCCTCTCACATACCCTTGAGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGA GCATAG199 4F75CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAACCTGGGGGTTCTCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTCAGGAACTATGCAATGAGCTGGGTCCGTCAGGCTCCAGGAAAGGGGCTCGAGTGGGTCTCAACTATTAATGGTGGTGGTGGTATCACAAGCTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACAATGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTCTATTACTGTGCCCAAACCGCCCGCGATTCCCGCGATTCCCGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 200 3F59CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAACCTGGGGGTTCTCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTCAGTAGCTATGCTATGAGCTGGGTCCGCCTGGCTCCAGGAAAGGGGCTCGAGTGGGTCTCAACTATTAATATCGCTGGTGGTATCACAAGCTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTGTATTACTGTGCAAAAACGGCGGCCAACTGGAGCGCCCAGAGAGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 201 4F78CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAACCTGGGGGTTCTCTGAGACTCTCCTGTGCAGCCTCTGGATTCACCTTCAGTAGCTATGCTATGAGCTGGGTCCGCCAGGCTCCAGGAAAGGGGCTCGAGTGGGTCTCAACTATTAATATGGGTGGTGGTACCACAAGCTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGACACAACGCCAAGAACACGCTGTATCTGCAAATGAACAGCCTGAAACCTGAGGACACGGCCGTGTATTACTGTGCAAAAACGGCGGGCAACTGGAGCGCCCAGAGAGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 202 3F1CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAACCTGGGGGTTCTCTGAGACTGTCCTGTGCAGCCTCTGGATTCACCTTCAGTACAAGTGCCATGAGTTGGATCCGCCAGCCTCCAGGGAAGGCGCGCGAGGTGGTCGCAACTATTACTAGTGCTGGTGGTAGTATAAGTTATGTAAACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGCTGTATCTGCAAATGAACATGCTGAAACCTGAGGACACGGCCGTGTATTACTGTGCCCGACTGGTCAACCTTGCCCAGACCGGCCAGGGAACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGA GCATAG203 3F65CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCCTGGTGCAACCTGGGGGTTCTCTGAGACTGTCCTGTGCAGCCTCTGGATTCACCTTCAGTACAAATGCCATGAGTTGGATCCGCCAGCCTCCAGGGAAGGCGCGCGAGGTGGTCGCAACTATTACTAGTGCTGGTGGTAGTATAAGTTATGTAAACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGCTGTATCTGCAAATGAACATGCTGAAACCTGAGGACACGGCCGTGTATTACTGTGCCCGACTGGTCAACCTTGCCCAGACCGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGA GCATAG

TABLE 7 Y. pestis LcrV SAb Protein Sequences SEQ ID NO Name Sequence 2041LCRV32QVQLQESGGGMVEPGGSLRLSCAASGFRFSSYAMSWVRQAPGKGLERVSAINSDGDKTSYADSVKGRFTISRDNARNTLYLQMSNLKPEDTAVYYCADRDLYCSGSMCKDVLGGARYDFRGQGTQVTVSS 2052LCRV4QVQLQESGGGLVEPGGSLRLSCAASGFRFSSYAMSWVRQAPGKGLERVSAINSDGDKTSYADSVKGRFTISRDNARNTLYLQMSNLKPEDTAVYYCADRDLYCSGSMCKDVLGGARYDFRGQGTQVTVSS 2062LCRV3QVQLQESGGGMVEPGGSLRLSCAASGFRFSSYAMSWVRQAPGKGLERVSAINSDGDKTSYADSVKGRFTISRDNARNTLYLQMNNLKPEDTAVYYCADRDLYCSGSMCKDVLGGARYDFRGQGTQVTVSS 2071LCRV52QVQLQESGGGLVQSGESLRLSCAASGLRFSSYAMSWVRQAPGKGLERVSAINSDGDKTSYADSVKGRFTISRDNARNTLYLQMSNLKPEDTAVYYCADRDLYCSGSMCKDVLGGARYDFRGQGTQVTVSS 2081LCRV4 QVQLQESGGGLVQPGGSLKLSCAASGFTFNWYTMAWYRQVPGEERKMVATITGASGDTKYADSVKGRFTISRDNAKNTVTLQMNSLKPGDAAVYYCHAYLTYDSGSVKGVNYWGQGTQVTVSS 209 1LCRV13QVQLQESGGGLVRPGGSLKLSCAASGFTFNWYTMAWYRQVPGEERKMVATITGASGDTKYADSVKGRFTISRDNAKNTVTLQMNSLKPGDTAVYYCHAYLTYDSGSVKGVNYWGQGTQVTVSS 210 2LCRV1QVQLQESGGGSVQPGGSLKLSCAASGFTFNWYTMAWYRQVPGEERKMVATITGASGDTKYADSVKGRFTISRDNAKNTVTLQMNSLKPGDTAVYYCHAYLTYDSGSVKGVNYWGQGTQVTVSS 211 1LCRV81QVQLQESGGGSVQPGGSLKLSCAASGFTFNWYTMAWYRQVPGEERKMVATITGASGDTKYADSVKGRSTISRDNAKNTVTLQMNSLKPGDTAVYYCHACLTYDSGSVKGVNYWGQGTQVTVSS 212 1LCRV27QVQLQESGGGFVQPGGSLKLSCAASGFTFNWYTMAWYRQVPGEERKMVATITGASGDTKYADSVKGRFTISRDNAKNTVTLQMNSLKPGDTAVYYCHAYLTYDSGSVKGVNYWGQGTQVTVSS 213 1LCRV34QVQLQESGGGLVQPGGSLKLSCAASGFTFNWYTMAWYRQVPGEERKMVATITGASGDTKYADSVKGRFTISRDNAKNTVTLQMNSLKPGDTAVYYCHAYLTYDSGSAKGVNYWGQGTQVTVSS 214 1LCRV31QVQLQESGGGLVQPGGSLGLSCAASGSLLNIYAMGWYRQAPGRQRELVATVTSSGTAEYADSVKGRFTISRDNAKNTVYLQMNSLRPEDTGVYYCNAHLRYGDYVRGPPEYNYWGQGTQVTVSS 215 1LCRV28QVQLQESGGGLVQPGGSLRLSCAASGGTLGYYAIGWFRQAPGKEREAVSCITSSDTSAYYADSAKGRFTISRDNAKNTMYLQMNNLKPEDTAVYYCAAGYYFRDYSDSYYYTGTGMKVWGKGTQVTVSS 2162LCRV11QVQLQESGGGLVQPGGSTRLSCAASGFTLDIYAIGWFRQAPGKEHEGVSWIVGNDGRTYYIDSVKGRFTISRDNAKNTVYLEMNSLKPEDTAVYYCAAKFWPRYYSGRPPVGRDGYDYWGQGTQVTVSS 2171LCRV47QVQLQESGGGLVQPGGSLILSCTISGASLRDRRVTWSRQGPGKSLEIIAVMAPDYGVHYFGSLEGRVAVRGDVVKNTVYLQVNALKPEDTAIYWCSMGNIRGLGTQVTVSS

TABLE 8 Y. pestis LcrV SAb DNA Sequences SEQ ID NO Name Sequence 2181LCRV32 CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCATGGTAGAACCTGGGGGTTCTCTGAGACTCTCCTGTGCAGCCTCTGGATTCCGCTTCAGTAGTTATGCTATGAGTTGGGTCCGCCAGGCTCCAGGAAAGGGGCTCGAGCGGGTCTCGGCTATTAATAGTGATGGTGATAAAACAAGCTATGCAGACTCCGTGAAGGGCCGATTTACCATCTCCAGAGACAACGCCAGGAACACGCTGTATCTGCAAATGAGCAACCTGAAACCTGAAGACACGGCCGTGTATTACTGTGCAGACCGAGATTTGTACTGTTCAGGCTCTATGTGTAAGGACGTCTTGGGGGGAGCACGCTATGACTTTCGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 219 2LCRV4CAGGTGCAGCTGCAGGAGTCTGGAGGAGGCTTGGTAGAACCTGGGGGTTCTCTGAGACTCTCCTGTGCAGCCTCTGGATTCCGCTTCAGTAGTTATGCTATGAGTTGGGTCCGCCAGGCTCCAGGAAAGGGGCTCGAGCGGGTCTCAGCTATTAATAGTGATGGTGATAAAACAAGCTATGCAGACTCCGTGAAGGGCCGATTTACCATCTCCAGAGACAACGCCAGGAACACGCTGTATCTGCAAATGAGCAACCTGAAACCTGAAGACACGGCCGTGTATTACTGTGCAGACCGAGATTTGTACTGTTCAGGCTCTATGTGTAAGGACGTCTTGGGGGGAGCACGCTATGACTTTCGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 220 2LCRV3CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCATGGTAGAACCTGGGGGTTCTCTGAGACTCTCTTGTGCAGCCTCTGGATTCCGCTTCAGTAGTTATGCTATGAGTTGGGTCCGCCAGGCTCCAGGAAAGGGGCTCGAGCGGGTCTCGGCTATTAATAGTGATGGTGATAAAACAAGCTATGCAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAGGAACACGCTGTATCTGCAAATGAACAACCTGAAACCTGAAGACACGGCCGTGTATTACTGTGCAGACCGAGATTTGTACTGTTCGGGCTCTATGTGTAAGGACGTCTTGGGGGGAGCACGCTATGACTTTCGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 221 1LCRV52CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGTCTGGCGAGTCTCTCAGACTCTCCTGTGCAGCCTCTGGACTCCGCTTCAGTAGTTATGCTATGAGTTGGGTCCGCCAGGCTCCAGGAAAGGGGCTCGAGCGGGTCTCGGCTATTAATAGTGATGGTGATAAAACAAGCTATGCAGACTCCGTGAAGGGCCGATTTACCATCTCCAGAGACAACGCCAGGAACACGCTGTATCTGCAAATGAGCAACCTGAAACCTGAAGACACGGCCGTGTATTACTGTGCAGACCGAGATTTGTACTGTTCAGGCTCTATGTGTAAGGACGTCTTGGGGGGAGCACGCTATGACTTTCGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 222 1LCRV4CAGGTGCAGCTGCAGGAGTCTGGAGGAGGCCTGGTGCAGCCTGGGGGGTCTCTGAAACTCTCCTGTGCAGCCTCTGGATTCACCTTCAATTGGTATACCATGGCCTGGTATCGCCAGGTTCCAGGGGAGGAGCGCAAAATGGTCGCCACAATTACAGGTGCTAGTGGTGACACAAAATATGCAGACTCCGTGAAGGGCCGGTTCACCATCTCCAGAGACAATGCCAAGAACACGGTGACACTGCAAATGAACAGCCTTAAACCTGGAGACGCGGCCGTCTATTACTGTCATGCCTACCTAACCTACGACTCGGGGTCCGTCAAAGGAGTTAACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 223 1LCRV13CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCGGCCTGGGGGGTCTCTGAAACTCTCCTGTGCAGCCTCTGGATTCACCTTCAATTGGTATACCATGGCCTGGTATCGCCAGGTTCCAGGGGAGGAGCGCAAAATGGTCGCCACAATTACAGGTGCTAGTGGTGACACAAAATATGCAGACTCCGTGAAGGGCCGGTTCACCATCTCCAGAGACAATGCCAAGAACACGGTGACACTGCAAATGAACAGCCTTAAACCTGGAGACACGGCCGTCTATTACTGTCATGCCTACCTAACCTACGACTCGGGGTCCGTCAAAGGAGTTAACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 224 2LCRV1CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTCGGTGCAGCCTGGGGGGTCTCTGAAACTCTCCTGTGCAGCCTCTGGATTCACCTTCAATTGGTATACCATGGCCTGGTATCGCCAGGTTCCAGGGGAGGAGCGCAAAATGGTTGCCACAATTACAGGTGCTAGTGGTGACACAAAATATGCAGACTCCGTGAAGGGCCGGTTCACCATCTCCAGAGACAATGCCAAGAACACGGTGACACTGCAAATGAACAGCCTTAAACCTGGAGACACGGCCGTCTATTACTGTCATGCCTACCTAACCTACGACTCGGGGTCCGTCAAAGGAGTTAACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 225 1LCRV81CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTCGGTGCAGCCTGGGGGGTCTCTGAAACTCTCCTGTGCAGCCTCTGGATTCACCTTCAATTGGTATACCATGGCCTGGTATCGCCAGGTTCCAGGGGAGGAGCGCAAAATGGTCGCCACAATTACAGGTGCTAGTGGTGACACAAAATATGCAGACTCCGTGAAGGGCCGGTCCACCATCTCCAGAGACAATGCCAAGAACACGGTGACACTGCAAATGAACAGCCTTAAACCTGGAGACACGGCCGTCTATTACTGTCATGCCTGCCTAACCTACGACTCGGGGTCCGTCAAAGGAGTTAACTACTGGGGTCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 226 1LCRV27CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTCGTGCAGCCTGGGGGGTCTCTGAAACTCTCCTGTGCAGCCTCTGGATTCACCTTCAATTGGTATACCATGGCCTGGTATCGCCAGGTTCCAGGGGAGGAGCGCAAAATGGTCGCCACAATTACAGGTGCTAGTGGTGACACAAAATATGCAGACTCCGTGAAGGGCCGGTTCACCATCTCCAGAGACAATGCCAAGAACACGGTGACACTGCAAATGAACAGCCTTAAACCTGGAGACACGGCCGTCTATTACTGTCATGCCTACCTAACCTACGACTCGGGGTCCGTCAAAGGAGTTAACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 227 1LCRV34CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCCTGGTGCAGCCTGGGGGGTCTCTGAAACTCTCCTGTGCAGCCTCTGGATTCACCTTCAATTGGTATACCATGGCCTGGTATCGCCAGGTTCCAGGGGAGGAGCGCAAAATGGTCGCCACAATTACAGGTGCTAGTGGTGACACAAAATATGCAGACTCCGTGAAGGGCCGGTTCACCATCTCCAGAGACAATGCCAAGAACACGGTGACACTGCAAATGAACAGCCTTAAACCTGGAGACACGGCCGTCTATTACTGTCATGCCTACCTAACCTACGACTCGGGGTCCGCCAAAGGAGTTAACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 228 1LCRV31CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGGGGGTCTCTAGGACTCTCCTGTGCAGCCTCTGGAAGCCTCTTAAATATCTATGCCATGGGCTGGTACCGCCAGGCTCCAGGGAGACAGCGCGAGTTGGTCGCAACTGTAACGAGTAGTGGAACCGCAGAATATGCAGACTCCGTGAAGGGCCGATTCACCATCTCTAGAGACAACGCCAAGAACACGGTGTATCTGCAAATGAACAGCCTGAGACCTGAGGACACGGGCGTCTATTACTGTAATGCACATCTCAGATATGGCGACTATGTCCGTGGCCCTCCGGAGTATAACTACTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 229 1LCRV28CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGGGGGTCTCTGAGACTCTCCTGTGCAGCCTCTGGAGGCACTTTGGGTTACTATGCCATAGGCTGGTTCCGCCAGGCCCCAGGGAAGGAGCGCGAGGCGGTCTCCTGTATTACTAGTAGTGACACTAGCGCATACTATGCAGACTCCGCGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGATGTATCTGCAAATGAACAACCTGAAACCTGAGGACACAGCCGTTTATTACTGTGCAGCCGGTTACTATTTTAGAGACTATAGTGACAGTTACTACTACACGGGGACGGGTATGAAAGTCTGGGGCAAAGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 230 2LCRV11CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGGGGGTCTACGAGACTCTCCTGTGCAGCCTCTGGATTCACTTTGGATATTTATGCTATAGGCTGGTTCCGCCAGGCCCCAGGGAAGGAGCATGAGGGGGTCTCGTGGATTGTTGGTAATGATGGTAGGACATACTACATAGACTCCGTGAAGGGCCGATTCACCATCTCCAGAGACAACGCCAAGAACACGGTGTATCTTGAAATGAACAGCCTGAAACCTGAGGATACAGCCGTTTATTACTGCGCAGCTAAGTTCTGGCCCCGATATTATAGTGGTAGGCCTCCAGTAGGGAGGGATGGCTATGACTATTGGGGCCAGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG 231 1LCRV47CAGGTGCAGCTGCAGGAGTCTGGGGGAGGCTTGGTGCAGCCTGGCGGGTCTCTGATACTCTCCTGTACAATCTCGGGAGCCTCGCTCCGAGACCGACGCGTCACCTGGAGTCGCCAAGGTCCAGGGAAATCGCTTGAGATCATCGCAGTTATGGCGCCGGATTACGGGGTCCATTACTTTGGCTCCCTGGAGGGGCGAGTTGCCGTCCGAGGAGACGTCGTCAAGAATACAGTATATCTCCAAGTAAACGCCCTGAAACCCGAAGACACAGCCATCTATTGGTGCAGTATGGGGAATATCCGGGGCCTGGGGACCCAGGTCACCGTCTCCAGCGGCCGCTACCCGTACGACGTTCCGGACTACGGTTCCGGCCGAGCATAG

TABLE 9 F1 SAb Groups Group Name SEQ ID NO 1 3F55, 3F85 168, 169 2 3F44170 3 3F31, 3F61, 4F1, 4F6, 4F34 171-175 4 4F27 176 5 3F26 177 6 4F59178 7 3F5, 4F57 179-180 8 4F75 181 9 3F59, 4F78 182-183 10 3F1, 3F65184-185

TABLE 10 LcrV SAb Groups Group Name SEQ ID NO 1 1LCRV32, 2LCRV4, 2LCRV3,1LCRV52 204-207 2 1CLRV4, 1LCRV13, 2LCRV1, 1LCRV81, 208-213 1LCRV27,1LCRV34 3 1LCRV31 214 4 1LCRV28 215 5 2LCRV11 216 6 1LCRV47 217

TABLE 11 Binding Kinetics of LcrV and F1 Sabs BIACORE K_(D) MicrocalK_(D) Name SEQ ID NO (nM) (nM) 1LCRV13 209 0.00063 3.2 1LCRV28 215 0.190.20 1LCRV31 214 0.0019 0.76 1LCRV32 204 22 26 1LCRV47 217 >1000 no heat1LCRV81 211 3.5 Error 2LCRV11 216 8.2 Error 3F1 184 97 110 3F5 179 47 833F26 177 — — 3F44 170 — — 3F55 168 2.2 190 3F59 182 5.9 no heat 3F61 17568 290 3F85 169 15 110 4F1 173 520 error 4F6 172 34 80 4F27 176 — — 4F34171 390 error 4F59 178 27 83 4F75 181 6/9  error 4F78 183 6/28 error

TABLE 12 Binding Constants of LcrV SAbs Name SEQ ID NO k_(a) (M⁻¹ s⁻¹)k_(d) (s⁻¹) K_(D) (nM) 1LCRV13 209 2.5 × 10⁵ 1.6 × 10⁻⁶ 0.00063 1LCRV28215 4.3 × 10⁵ 8.1 × 10⁻⁵ 0.19 1LCRV31 214 1.7 × 10⁵ 3.1 × 10⁻⁷ 0.00191LCRV32 204 3.4 × 10⁵ 7.3 × 10⁻³ 22 1LCRV47 217 n.b. n.b. — 1LCRV81 2111.8 × 10⁵ 6.3 × 10⁻⁴ 3.5 2LCRV11 216 8.8 × 10⁵ 7.2 × 10⁻³ 8.2

Although specific embodiments have been described in detail in theforegoing description and illustrated in the drawings, various otherembodiments, changes, and modifications to the disclosed embodiment(s)will become apparent to those skilled in the art. All such otherembodiments, changes, and modifications are intended to come within thespirit and scope of the appended claims.

What is claimed is:
 1. A single-domain antibody against Yersinia pestis(Y. pestis) F1 protein comprising: a first framing region (“FR”)sequence comprising SEQ ID No:90 or SEQ ID No:92; a firstcomplementarity determining region (“CDR”) sequence comprising SEQ IDNo:15; a second FR sequence comprising SEQ ID No:112, the first CDRsequence being positioned between the first FR sequence and the secondFR sequence; a second CDR sequence comprising SEQ ID No:42 or SEQ IDNo.43; a third FR sequence comprising SEQ ID No: 134, the second CDRsequence being positioned between the second FR sequence and the thirdFR sequence; a third CDR sequence comprising SEQ ID No.67; and a fourthFR sequence comprising SEQ ID No:151, the third CDR sequence beingpositioned between the third FR sequence and the fourth FR sequence. 2.The single-domain antibody of claim 1, wherein the at least onesingle-domain antibody further comprises: at least one of a protein tag,a protein domain tag, or a chemical tag.
 3. The single-domain antibodyof claim 1, further comprising: a plurality of single-domain antibodies,wherein the single-domain antibodies of the plurality are against the Y.pestis F1 protein and a Y. pestis YscF protein or a Y. pestis LcrVprotein.
 4. A polypeptide comprising: a plurality of the single-domainantibodies of claim 1 organized into a chain.
 5. The polypeptide ofclaim 4, wherein at least a portion of the plurality of single-domainantibodies comprising the polypeptide is against a different epitope onthe F1 protein.
 6. The polypeptide of claim 4, wherein the plurality ofsingle-domain antibodies comprising the polypeptide is against the Y.pestis F1 protein and a Y. pestis YscF protein or a Y. pestis LcrVprotein.
 7. The polypeptide of claim 4, further comprising: a fusionprotein.
 8. The polypeptide of claim 4, further comprising: amultivalent protein complex such that the single-domain antibodies ofthe plurality are joined together with at least one linker molecule. 9.The polypeptide of claim 4, wherein at least one of the plurality ofsingle-domain antibodies comprising the polypeptide further comprises:at least one of a protein tag, a protein domain tag, or a chemical tag.10. At least one isolated nucleotide sequence encoding the at least onesingle-domain antibody of claim 1, wherein the isolated nucleotidesequence is selected from the group consisting of SEQ ID No:179 or SEQID No:180.